In semiconductor technologies, image sensors are used for sensing a volume of exposed light projected towards the semiconductor substrate. Complementary metal-oxide-semiconductor (CMOS) image sensor devices are widely used in various applications such as digital still camera (DSC) applications. These devices utilize an array of active pixels or image sensor cells, including photodiode and MOS transistors, to collect photo energy to convert images to streams of digital data. However, when image sensor pixels get smaller and smaller in advanced technology nodes, existing image sensor devices suffer various issues including degraded sensitivity, image lag and electrical cross-talk. Improvements of the image sensor and the corresponding substrate are desired.